CHAPTER-II Study Area 2. STUDY AREA __________________________________________________________________________________ 2.1 Study area (sub-Himalayan hotspot region of North Bengal, West Bengal, India). North Bengal (In Bengali language: ―Uttarbanga‖) is a region that encompass Northern part of West Bengal and denotes Cooch Behar, Darjeeling, Jalpaiguri, Alipurduar, North Dinajpur, South Dinajpur and Malda districts collectively. It additionally includes parts of Darjeeling Hills. Traditionally, the Hooghly River divides West Bengal into North and South Bengal. North Bengal is in addition divided once more into Terai and Dooars regions. North Bengal can be broadly divided in three sections i.E., the hills consisting of Darjeeling, Kalimpong, Kurseong and Mirik, the plains of Cooch Behar and Malda and the ultimate phase is the Terai place which include Dooars which is the stretch from of the foothills of Himalaya, additionally called sub-Himalayan place of West Bengal. The snow covered mountain peaks, the dense foothill, the luxuriant green forests, the frothing rivers, the luxurious crop fields, vibrant green tea gardens makes the terai and dooars of North Bengal a hotbed of bio-variety or biodiversity hotspot. Siliguri is the centre for buying and selling, tourism, tea and wood; and Jalpaiguri is the headquarter of Dooars. Siliguri is the gateway to the complete of North-East India that consists of seven states and also 4 neighbouring international locations (Nepal, Bangladesh, Bhutan, Tibet and China); and they have their global buying and selling course through Siliguri. This vicinity has many the worlds over famous locations and growing very fast and is hooked up to all of the most important cities or town all throughout the globe. The predominant reason for its infrastructural and the industrial increase is its strategic place. Tea, tourism, wood, transport and trading is probably the possible cause for the increasing development of this location. The region covers the moist and dense riverine forests of the Bengal Dooars (Duars) and the foothills of the snow covered Kanchenjunga range. The specific climatic and ecological situations make North Bengal a completely unique habitat for a massive wide variety of mega fauna and flowers. The altitudanal zones of plants run from tropical, sub tropical, moderate to Alpine – a few locations just 10 km in a right away line isolates the palm developing valleys from ceaseless snow. 2.1.1 Terai The Terai ("moist land") is a belt of mucky meadows, savannas, and woodlands at the bottom of the Himalaya that run in India, Nepal, and Bhutan, from the Yamuna River within Page | 69 the west to the Brahmaputra River in the east. Over the Terai belt lies the Bhabhar is made up of replacement layers of mud and sand; a forested belt of rock and soil disintegrated from the Himalaya mountain tiers. The excessive water table that lies from 5 to 37 meters down makes numerous springs and wetlands. The Terai zone is immersed every year by way of the rainstorm swollen river streams of the Himalaya. Underneath the Terai lies the good sized alluvial undeniable of the Yamuna, Ganges, Brahmaputra, and their tributaries. [Source: http://biodiversity-mohanpai.blogspot.in/2008/12/biodiversity-north-bengal.html] 2.1.2 Dooars The Dooars or Duars are flood plains at the foothills of the jap Himalayas in North- East India around Bhutan. In both Assamese and Bengali languages Duar means ―Door‖. It is the gateway to the North Eastern place of India. This area is divided via the Sankosh river into the eastern and the western Dooars, consisting of an area of 800 square kilometre. This vicinity became part of the Indian states of Assam and West Bengal. There are innumerable streams and rivers flowing thru those plains from the mountains of Bhutan make this undeniable very fertile. In Assam the foremost rivers are Brahmaputra and Manas, and in northern West Bengal the major river is the Teesta and plenty of others like the Jaldhaka, Murti, Ghotia, Torsha, Sankosh, Diana, Raidak, Kaljani etc. The forested regions of northern West Bengal gift a plenty of Wildlife. This blended dry deciduous woodland noticed with fields, harbors the biggest assorted kind of principal fauna in West Bengal. A huge range of foothill forest in North Bengal is referred to as Dooars. Tea Gardens, snow covered landscapes, honest streams; National Parks and the Wildlife Sanctuary make this area a paradise. Wonderful motorable streets slice via profound forest, wealthy with wild lifes. Gentle slopes stay toward the cease of velvet inexperienced fields and the woodland is echoed with the music of winged animals. Dooars is the territory of the unusual Toto clans. The maximum superb passage factor to Dooars is thru Siliguri by street. The primary spots of enthusiasm for Dooars are Jaldapara National Park and Gorumara National Park, Buxa National Park, Mahananda Wildlife Sanctuary, Rasik Bill Bird Sanctuary, Chapramari Wildlife Reserve, Chilapata forest, Jayanti hills, Bindu, Rocky Island. [Source: http://www.northeastindiatours.in] Page | 70 2.2 River systems The sub-Himalayan North Bengal region is intersected via numerous streams, rivers and rivulets. All their resources are the Darjeeling Himalaya in the north. The rivers in this place are in particular snow fed and rain endorsed. Due to their big catchment location most of the rivers drain good sized quantity of water throughout wet season. All rivers convey massive load of sediment with their water due to excessive price of soil disintegration occur inside the hill location. The greater part of the streams has excessive slope and big measure of water so they're used for the technology of hydroelectricity. Scarcely any hydroelectric ventures are brought in the sloping components of the streams. The streams are separated into high run-off region, excessive infiltration quarter and recharge quarter. Unreasonable rain, expansive catchment territory, low wearing limit and snow melted water all activates frequent floods within the streams. The rivers often changed their course of glide due to unexpected bursting of artificial water garage by using landslides and bank disintegration. High deforestation occurred due to human interference inside the hills and adjacent region of the Darjeeling place ends in soil degradation, erosion and common landslides which is the characteristic of Darjeeling hills. Many forests are cleared for tea plantation and terrace cultivation for production of plants; leaves last forest inside a danger because of populace enlargement changed into due to excessive rate of immigration from neighboring states and international locations. The rivers with their higher catchment inside the hills have funneled fashioned basin with narrow outlets on the foothills; inside the plains the rivers falls notably and unexpectedly widens. So to resist this condition the rivers adjust themselves by means of converting their courses from erosional to depositional nation to adjust the brand new hydrogeographical necessities brought on by way of the exchange of the gradients as rivers glide from excessive to lower altitude. Development of new channels, shifting of the channels and forsaking the old one are the most common inside the rivers of this place. Often, overflowing of water on one river reasons flood inside the catchment region of nearby rivers. The construction of longitudinal embankment along the rivers has reasons the rise of the river bed level that results in deposition of sediments in many locations of the river bed. This problem is augmented by way of careless diversion of water from rivers for irrigation inside the agricultural fields and different family purposes; these outcomes the rivers incompetent to hold silts and particles. Removal of boulders and twine-guards from the embankment weakens the embankment; consequently, the rivers end up unable to carry massive quantity of water at some point of wet season lead to floods within the nearby region. This activities reason intense financial institution erosion and therefore inundate the adjacent regions. Page | 71 Scarcity of appropriate habitats pressured the lowland inhabitants to settle their everlasting homes at the stretches river mattress or facets of the banks due to the fact the whole highlands are dedicated to cultivation of various vegetation and teas. Peoples with out a know-how approximately the nature of the North Bengal rivers also build their citizens at the lands which can be generally the beds of vintage abandoned channels. 2.2.1 Mahananda-Balasan River System Mahananda River is one of the essential tributary of the Ganga River within the eastern a part of India. The Mahananda River is a trans-boundary river and flows thru the Indian states of West Bengal, Bihar, and crosses Indian boundary to go into Bangladesh. Its proper bank tributary, the Mechi River paperwork part of Nepal's jap boundary with West Bengal, India; while the Kankai flows out of Nepal. The Mahananda originates within the Himalaya‘s Paglajhora Falls on Mahaldiram Hill near Chimli, east of Kurseong in Darjeeling district at an elevation of two,one hundred metres (6,900 ft) (Jain et al., 2010; "Rivers in Siliguri". Mahananda River. Siliguri on line. Retrieved 2010-05-14; "Rivers". Darjeeling News.Net. Retrieved 2010-05-14). It flows across the Mahananda Wildlife Sanctuary and descends to the fotthills of Himalayan plains near Siliguri and touches Jalpaiguri district ("Mahananda Wildlife Sanctuary". nature beyond. Retrieved 2010-05-14). It enters